Ipsen announced the preliminary results of a phase-I trial in metastatic breast cancer with BN83495, Ipsen’s lead and first-in-class orally available irreversible steroid sulfatase (STS) inhibitor. In the course of the study, the optimal biological dose was determined as 40 mg once daily oral administration for future phase-II trials in this indication.

Preliminary results were the subject of a poster (#4097) entitled 'A phase-I Dose Escalation Study of Steroid Sulfastase Inhibitor BN83495 (STX64) in Postmenopausal Women with ER- Positive Breast Cancer' presented at the 32nd San Antonio Breast Cancer Symposium held from December 9 to December 13, 2009, in San Antonio (Texas, USA).

The compound is currently in further clinical development for advanced endometrial cancer (phase-II) as well as in phase-I clinical evaluation for castrate resistant prostate cancer in North America.
Professor R Charles Coombes, Imperial College, Clinical professor, Division of Surgery, Oncology, Reproductive Biology and Anaesthetics London, UK, lead author of the poster said, "To date, four of the patients who received BN83495 had tumours that remained stable for at least six months. One of these had cutaneous metastases that improved after one month of treatment. This is very encouraging, as these women are patients who are reaching the end of their hormonal treatment options. Importantly, BN83495 was well tolerated at the selected dose.” He added, “I am confident that BN83495 will become a new hormonal option in the treatment of post-menopausal women with ER-positive metastatic breast cancer.”

Stéphane Thiroloix, executive vice-president, Corporate Development commented, “Metastatic breast cancer clearly deserves R&D effort to identify new hormonal agents that can delay disease progression and prolong overall survival. Following this important clinical milestone, we look forward to progressing the global development of BN83495 in this indication and in other selected hormone-dependent cancer indications. ”

Ipsen’s lead oncology development candidate, BN83495, is a first-in-class orally available irreversible steroid sulfatase (STS) inhibitor.

The SABCS is one of the largest annual symposium in the world devoted to breast cancer research and physician education.

Ipsen is an innovation-driven global specialty pharmaceutical group with over 20 products on the market and a total worldwide staff of nearly 4,200.